Positioning devices are generally known, e.g. from EP 0421527 A1, WO 2004/055607 A2 and WO 2007/057842 A1.
A known configuration of a high precision positioning device comprises two or more stages stacked on top of each other, where at least the top stage is full floating in 6 degrees of freedom. The top stage in this configuration typically has limited (up to 1 mm) strokes in the vertical directions and at least one limited stroke in the horizontal direction. The stages below this top stage will provide the long stroke in that direction.
The top stage typically holds an object to be positioned and often has a requirement to have a very stable temperature and a uniform temperature distribution as to not deform this object. Therefore it is important to limit the conduction of heat from the actuator to the rest of the top stage structure. Usually water cooling is used to transport the heat away from the actuator. This water cooling however forms a mechanical connection to the top stage and deteriorates the dynamic performance of the stage.